Problems with Ds1820

[Jan Middel]

Hallo,

I’m stil trying to get a temperature meter with a 1-wire component to work properly.
To do this I use a Dallas DS1820 together with the example program that is supplied with the Flowcode 4.
When I run the program, I only get the result -1. With a DS18B20 I get the same result (-1).
When I disconnect the PIC I get an exception “Device not found”. Therefore I believe there is a connection between the PIC and the DS1820.
There is a pull-up resistance of 4k7 between the power source and data connection.
The processor runs at 2,45679 Mhz, I also get the same result with other speeds. I’ve asked questions before and used the answers, but somehow I can’t get it to work the way I want it to.
I use the 16f877a with de Ds1820 connect at pin 0 from port A
Can anybody help me?


Jan

[Benj]

Hello Jan

Have you tried the example program available from here. It is working fine for me.

http://www.matrixmultimedia.com/mmforum ... =25#p15709